Day 22: Rates + follow up

Concept tests in both classes today. Student’s scores are always going up which is great to see. In Geometry we finished up some practice on conditional statements and inductive reasoning. I have not been following the textbook’s sequencing of these things and feel like it is going well. With logic, students need to practice bits and pieces of all kinds of reasoning at the same time rather than simply going through them as different concepts.

In Algebra I started with a number talk:

I swear I didn’t encourage any of this! Not even absolute value…

Last year I gave the same question but on May 18th or something and got this:

18 +0

17 + 1

16 + 2….

When we do number talks/visual patterns I tell students that I am only interested in how they are thinking about things, not the end result. It was really funky to begin with and students were uncomfortable with a focus other than the answer.

What I saw in the number talk today validated everything I have been doing this year.

After, students ranked the following from most expensive to least expensive.

A few students were hesitant and wanted to know how much of each, I kinda sorta ignored them. Then showed this:

This slide got them fired up; a bottle of water for $17.99?? What? Then they started asking what each of these were measured in.

Then they went to the power of Google to convert each into mL and re-rank the items. (Shout out to Dan for this idea)

A lot of times the blog post ends here and there isn’t much talk about the follow up. Well here is what I did.

In their notes, students wrote down the definition and examples of Ratio, Rate, and Unit Rate. We talked a little about how each of these tied into the activity. The vocab helps students communicate what they are finding; rather than saying I divided ______ by _______ they can now say I found the rate of $/mL and so on. The vocabulary is actually useful rather than just meaningless writing.

After the test I put up a few practice problems and on Monday we will continue to practice these concepts with the idea of proportions coming to surface.